Finishing of textile fabrics



P. FQCROSLAND FINISHING OF TEXTILE FABRICS Feb. 2, 1960 Filed Feb. 20, '1956 P f. b-Wm L Attorneys United tates Patent 1 2,923,047 FINISHING F TEXTILE FABRICS Percy Field Crosland, Bury, England Application February 20, 1956, Serial No. 566,674

Claims priority, application Great Britain February 22, 1955 1 Claim. (CI. 26-69) This invention relates to the finishing of cellulosic textile fabrics with the object of producing new or improved surface etfects thereon.

The art of mechanically pleating textile fabrics is well known and the effects produced can be divided in respect of their shape, into two main classes.

In the first class, the pleats or folds are produced by a reciprocating blade which folds the fabric into layers which are characterised by the fact that one layer of the fabric is always tucked over or under the next layer, such pleats being usually known as flat pleats.

In the second class the pleats are not tucked one under the other, but are zig-zag or sinuous in form. Folds or pleats of this type are often referred to as random and accordion pleats on textile fabrics. One way of producing such pleats or folds is to pass the fabric which may have been impregnated with a stiffened substance, between two contacting rollers driven at the same circumferential speed, which have their axes parallel and may have corrugated surfaces, and then peeling the pressed fabric from the rollers by pressure at the delivery side of the nip by means of knives or doctors. Pleats or folds produced by both the above well known methods have in common that the folds or pleats are substantially parallel and lie substantially at right angles to the selvedges or edges of the fabric.

It is often desired however and particularly so on textile fabrics, that the pleats shall not have this substantially parallel form, but shall diverge and take a shape which roughly approximates to the appearance of a flat section of a many spoked wheel. Pleats of this description are often applied to textile fabrics and are usually termed sun-ray pleats.

The present invention relates to the formation of such sun-ray pleats and it consists essentially in running the fabric between a pair of conical rollers which are heated, pressed together and driven at the same axial speed whereby the lineal speed of the fabric running between the rollers varies along the length of the rollers, the speed at any point being proportional to the diameter of the rollers at that point. Thus if a piece of fabric which has approximately the shape of a triangle with one corner cut off is passed between such a pair of driven conical squeezing rollers with its truncated end entering the nip near the point where the conical rollers have their minimum diameter, the pleats or folds produced by stripping the fabric from the delivery side of the nip by doctors will not be parallel but will be approximately radial in formation.

If instead of merely forming the pleats or folds by the stripping of the fabric after it has passed through the nip of the conical rollers, the latter are engraved with straight and regular grooves and ridges, a more desirable form of pleat or fold is produced. The grooves and ridges are deepest and widest at the large end of the roller and become shallower as they approach the small end thereof, and disappear completely at the small end of each roller or just before it.

The engraving of the two rollers of a pair must mesh so that the ridges of the one roller fit exactly into the grooves of its companion and when driven in this close contact run smoothly and without vibration.

When the fabric is cellulosic in nature if it is first impregnated with a solution containing impregnated materials which can produce thermo-setting resins, and dried, then by heating the fabric after it leaves the nip of the conical rollers, the folds or pleats can be made to acquire a high degree of durability.

If the fabric itself is of a thermo-plastic nature and can be deformed by heat, then without prior impregnation the passage of the fabric between the pair of engraved conical rollers running together under pressure and heated to the appropriate temperature will produce effects of high durability.

In order that the invention may be clearly understood reference will now be made to the accompanying drawings. In these drawings:

Fig. 1 is a diagrammatic view of a pair of conical rollers arranged with their axes inclined to one another through which the fabric is passed.

Fig. 2 is an end view of the large end of one of the rollers showing the grooves and ridges formed therein.

Fig. 3 is a section on line 3-3 of Fig. 1.

Fig. 4 is a section on line 4-4 of Fig. 1 (Figs. 2, 3 and 4 are drawn to a larger scale than Fig. 1) and Fig. 5 is a face view of a piece of fabric after treatment by the rollers.

As shown in Fig. 1, the two identical conical rollers A and B are pressed together and driven at the same axial speed.

As shown in Figs. 2, 3 and 4, the roller A is formed with straight regular ridges a and grooves a which are deepest and widest at the large end of the roller and gradually become shallower and narrower as they approach the small end of the roller, preferably disappearing just before the small end of the roller is reached.

Although only the roller A is shown in Figs. 2, 3 and 4, it is to be understood that the roller B is of corresponding construction so that the ridges of one roller will fit into the grooves of the other roller, and when driven in close contact the rollers will run smoothly and without vibration.

Fig. 5 illustrates a finished piece of fabric C with the random pleats or folds d formed therein.

I claim:

A method for the formation of sunray pleats in a cellulosic textile fabric, consisting essentially in the steps of impregnating a piece of textile fabric of triangular shape with one corner removed with a thermo-setting resin, drying the impregnated fabric, passing the dried fabric between a pair of driven conical rollers in pressure contact and having surfaces which are formed with intermeshing longitudinal grooves and ridges, the grooves in each roller being deepest and widest at the large end of the roller and becoming shallower and narrower and terminating as they approach the small end thereof so that pleats of corresponding shape and size are formed in said fabric, said fabric being passed between the rollers with said corner removed portion being located at the smaller ends of the rollers, maintaining said rollers s'ufiiciently heated as the fabric passes therebetween to set said resin and thereby permanently set the pleats substantially simultaneously with their forming, and stripping the fabric from the delivery side of the rollers, said fiinished fabric being completely pleated with the pleats radiating from said removed-comer portion.

References Cited in the file of this patent UNITED STATES PATENTS 563,962 Hinde July 14, 1896 1,428,064 Schuler Sept. 5, 1922 1,534,622 Wandel Apr. 21, 1925 1,617,018 Federhart Feb. 8, 1927 2,768,092 Lawrence Oct. 23, 1956 

